scholarly journals Effects of dry-wet cycles on three-dimensional pore structure and permeability characteristics of granite residual soil using X-ray micro computed tomography

2021 ◽  
Author(s):  
Ran An ◽  
Lingwei Kong ◽  
Xianwei Zhang ◽  
Chengsheng Li
Keyword(s):  
Computed Tomography ◽  
Pore Structure ◽  
Three Dimensional ◽  
Residual Soil ◽  
Micro Computed Tomography ◽  
X Ray ◽  
Permeability Characteristics ◽  
Granite Residual Soil

scholarly journals 3D immersive visualization of micro-computed tomography and XRD texture datasets

2019 ◽  
Vol 34 (2) ◽  
pp. 97-102
Author(s):  
M. A. Rodriguez ◽  
T. T. Amon ◽  
J. J. M. Griego ◽  
H. Brown-Shaklee ◽  
N. Green
Keyword(s):  
Computed Tomography ◽  
Texture Analysis ◽  
Mechanical Strain ◽  
Three Dimensional ◽  
Multidimensional Analysis ◽  
Micro Computed Tomography ◽  
X Ray ◽  
3D Data ◽  
Pole Figures ◽  
Ct Data

Advancements in computer technology have enabled three-dimensional (3D) reconstruction, data-stitching, and manipulation of 3D data obtained on X-ray imaging systems such as micro-computed tomography (μ-CT). Likewise, intuitive evaluation of these 3D datasets can be enhanced by recent advances in virtual reality (VR) hardware and software. Additionally, the generation, viewing, and manipulation of 3D X-ray diffraction datasets, such as pole figures employed for texture analysis, can also benefit from these advanced visualization techniques. We present newly-developed protocols for porting 3D data (as TIFF-stacks) into a Unity gaming software platform so that data may be toured, manipulated, and evaluated within a more-intuitive VR environment through the use of game-like controls and 3D headsets. We demonstrate this capability by rendering μ-CT data of a polymer dogbone test bar at various stages of in situ mechanical strain. An additional experiment is presented showing 3D XRD data collected on an aluminum test block with vias. These 3D XRD data for texture analysis (χ, ϕ, 2θ dimensions) enables the viewer to visually inspect 3D pole figures and detect the presence or absence of in-plane residual macrostrain. These two examples serve to illustrate the benefits of this new methodology for multidimensional analysis.

Region-of-Interest X-Ray Tomography for the Non-Destructive Characterization of Local Fiber Orientation in Large Fiber Composite Parts

2019 ◽  
Vol 809 ◽  
pp. 587-593
Author(s):  
Simon Zabler ◽  
Katja Schladitz ◽  
Kilian Dremel ◽  
Jonas Graetz ◽  
Dascha Dobrovolskij
Keyword(s):  
Computed Tomography ◽  
Spatial Resolution ◽  
Fiber Orientation ◽  
Fiber Composite ◽  
Three Dimensional ◽  
Region Of Interest ◽  
Micro Computed Tomography ◽  
X Ray ◽  
Anisotropic Thermal Conductivity ◽  
Local Fiber

To detect and characterize materials defects in fiber composites as well as for evaluatingthe three-dimensional local fiber orientation in the latter, X-ray micro-CT is the preferred methodof choice. When micro computed tomography is applied to inspect large components, the method isreferred to as region-of-interest computed tomography. Parts can be as large as 10 cm wide and 1 mlong, while the measurement volume of micro computed tomography is a cylinder of only 4 − 5 mmdiameter (typical wall thickness of fiber composite parts). In this report, the potentials and limits ofregion-of-interest computed tomography are discussed with regard to spatial resolution and precisionwhen evaluating defects and local fiber orientation in squeeze cast components. The micro computedtomography scanner metRIC at Fraunhofer‘s Development Center X-ray Technology EZRT deliversregion-of-interest computed tomography up to a spatial resolution of 2 μm/voxel, which is sufficientfor determining the orientation of natural or synthetic fibers, wood, carbon and glass. The mean localfiber orientation is estimated on an isotropic structuring element of approximately 0.1 mm length bymeans of volume image analysis (MAVI software package by Fraunhofer ITWM). Knowing the exactlocal fiber orientation is critical for estimating anisotropic thermal conductivity and materials strength.

scholarly journals Pore structure characterization of oak via X-ray computed tomography

BioResources ◽  
2020 ◽  
Vol 15 (2) ◽  
pp. 3053-3063
Author(s):  
Liangyan Guo ◽  
Hongchao Cheng ◽  
Junfeng Chen ◽  
Wentao Chen ◽  
Jingyao Zhao
Keyword(s):  
Computed Tomography ◽  
Pore Structure ◽  
Pore Size ◽  
Three Dimensional ◽  
Structure Characterization ◽  
X Ray ◽  
Volume Porosity ◽  
Pore Area ◽  
X Ray Computed ◽  
Area And Volume

The microscopic pore structure of wood is an important factor that affects its macroscopic properties. In this study, an oak sample was used for pore structure characterization. X-ray computed tomography imaging was carried out, and the scanning results (a multi-layer two-dimensional planar image) were rendered using Avizo software (a three-dimensional stereo image). A digital image processing method was used to identify the characteristics of the three-dimensional pore structure features and to calculate the characteristic parameters, i.e., the porosity (volume/surface), pore area and volume, pore size distribution, and the connectivity. The 27 mm3 oak sample had the following characteristics: a pore size which ranged from 8.56 µm to 1262.84 µm; a pore volume of 1.01 × 1010 µm3; a pore area and volume porosity of 1.12 × 109 µm2 and 37.6%, respectively; a surface porosity range of approximately 36.1% to 39.1%; a pore diameter for axial connection ranging from approximately 164.57 µm to 1262.84 µm; and had corresponding proportions of the pore area and volume of approximately 74.4% and 67.3%, respectively. This information provided useful structural data for the construction of future models.

High-Resolution Radiography for Detecting and Measuring Micron-Scale Features

2004 ◽  
Author(s):  
Daniel H. Morse ◽  
Arlyn J. Antolak ◽  
Bernice E. Mills
Keyword(s):  
Computed Tomography ◽  
Composite Materials ◽  
Phase Contrast ◽  
Three Dimensional ◽  
Conventional Radiography ◽  
Small Scale ◽  
Micro Computed Tomography ◽  
Contrast Imaging ◽  
X Ray ◽  
Projection Radiography

X-ray radiography has long been recognized as a valuable tool for detecting internal features and flaws. Recent developments in microfabrication and composite materials have extended inspection requirements to the resolution limits of conventional radiography. Our work has been directed toward pushing both detection and measurement capabilities to a smaller scale. Until recently, we have used conventional contact radiography, optimized to resolve small features. With the recent purchase of a nano-focus (sub-micron) x-ray source, we are now investigating projection radiography, phase contrast imaging and micro-computed tomography (μ-CT). Projection radiography produces a magnified image that is limited in spatial resolution mainly by the source size, not by film grain size or detector pixel size. Under certain conditions phase contrast can increase the ability to resolve small features such as cracks, especially in materials with low absorption contrast. Micro-computed tomography can provide three-dimensional measurements on a micron scale and has been shown to provide better sensitivity than simple radiographs. We have included applications of these techniques to small-scale measurements not easily made by mechanical or optical means. Examples include void detection in meso-scale nickel MEMS parts, measurement of edge profiles in thick gold lithography masks, and characterization of the distribution of phases in composite materials. Our work, so far, has been limited to film.

scholarly journals Micro-CT study of Middle Ordovician Spumellaria (radiolarians) from western Newfoundland, Canada

2020 ◽  
Vol 94 (3) ◽  
pp. 417-435 ◽  
Author(s):  
Sarah Kachovich ◽  
Jonathan C. Aitchison
Keyword(s):  
Computed Tomography ◽  
Three Dimensional ◽  
Detailed Examination ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Lower Paleozoic ◽  
X Ray ◽  
Middle Ordovician ◽  
Radiolarian Assemblage ◽  
Taxonomic Groups

AbstractA new, previously undescribed Middle Ordovician (middle Darriwilian: Dw2) radiolarian assemblage has been recovered from the Table Cove Formation at Piccadilly Quarry, western Newfoundland. Constituents of the fauna described herein are both distinctive and exceptionally well preserved. Three-dimensional X-ray micro-computed tomography (μ-CT) is used to make a detailed examination of four key spumellarian specimens. This technology enables visualization of hitherto ambiguous details of the internal morphologies of key lower Paleozoic taxonomic groups, among which a lack of knowledge has impeded resolution of higher taxonomic rankings.

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